Finding the distance, currency, temperature units etc. for a country (iPhone)

During the localization of my app I went through a lot of documentation, somewhere Im sure I read that there is a way to get a set of units that is linked with the locale.

I believe it said something like "units based on cultural..." something.

I would like to display temperature and distance in Fahrenheit and Miles for some countries and Celsius and Kilometers for other countries.

Is there a way to access a list of these units in the iPhone SDK.

Thanks you.